A Micro Electro Mechanical Systems (MEMS) microphone electronic component includes a moveable compliant diaphragm and a rigid perforated backplate on a silicon substrate. The diaphragm and backplate form a capacitor. As sound waves move the diaphragm, the capacitance between the diaphragm and backplate changes. The capacitance variations are converted into an electrical signal. In this manner, sound waves are converted into an electrical signal.
To optimize the sensitivity of the MEMS microphone electronic component, it is ideal to have a balanced front volume, defined by the space wherein the sound source and the front of the diaphragm belong, and back volume, defined by the space below the diaphragm and the substrate surface where the MEMS microphone electronic component is attached to. Typically the back volume in a MEMS microphone package design is limited by the available space below the diaphragm. It is therefore desirable in the MEMS microphone package design to increase the back volume to achieve higher performance.
In the following description, the same or similar elements are labeled with the same or similar reference numbers.